Current
Control
Phase
Control
One
Shot
Comp.
3718
+38V
A
R4 Typ
Phase
I
0
current
I
1
current
V
REF
0v
5v
0.4v
30v
30v
≈
2.7 mSec
00
U20 - 15
R4
J2 - 1
J2 – 3
A
B
C
D
Fig. 4.1 Stepper Motor Drive Circuit
B
0v
5v
0.4v
30v
30v
≈
2.7 mSec
00
U20 - 15
R4
J2 - 1
J2 – 3
A
B
C
D
0v
5v
0.0v
0.4v
0v
38v
38v
≈
2.7 mSec
00
≈
5.5 mSec
U20 - 15
R4
J2 - 1
J2 – 3
A
B
C
D
0v
C
D